1. Field of the Invention
This invention relates to hair spray compositions, and, more particularly, to a 0% VOC, single phase hair spray composition of a water-insoluble polymer wherein substantially all particles therein have a diameter of less than 1 micron, i.e. a microemulsion.
2. Description of the Prior Art
Hair spray compositions generally are solutions of a hair fixative polymer and a solvent, usually ethanol, water or ethanol-water mixtures, as described in U.S. Pat. Nos. 4,543,249; 4,798,721; 4,923,694; 4,985,239; 5,266,308; 5,085,859; 5,173,290; 5,176,898; and PCT WO 93/03705. Such compositions also may contain small quantities of one or more adjuvants normally found in cosmetic products including a small quantity of a surfactant. The presence of a surfactant in a hair spray composition reduces the surface tension between the aqueous and polymer phases in the composition, and provides sprays having a desirable small droplet size or mist. U.S. Pat. Nos. 4,543,249 and 5,176,898, for example, describe such a surfactant-containing system for water-soluble fixative polymers. Similarly, U.S. Pat. No. 5,085,859 discloses a hair treating composition containing a film-forming material which is an interpenetrating polymer network of a substituted vinyl copolymer having a polar functionality and a non-polar silsesquioxane. This patent suggests that the interpenetrating polymer might be incorporated into the composition as an emulsion or microemulsion; however, such formulations are not disclosed for an interpenetrating polymer, or for any other polymer.
Water-insoluble polymers, such as the ethyl and butyl half-esters of copolymers of maleic anhydride and methyl vinyl ether, known as GANTREZ.RTM.-ES resins, and sold by International Specialty Products (Wayne, N.J.), have been used for many years as the hair fixative resin of choice in alcohol-based hair spray compositions, both in non-aerosol (pump) and aerosol (propellant) delivery systems. Recent California state legislation, however, has required that future commercial hair spray compositions contain a low volatile organic compound (VOC) content therein, particularly 80% or less VOC (by 1994) and 55% or less VOC (by 1998). In order to meet these strict VOC standards, it has been necessary for hair spray formulators to substantially reduce the alcohol content and to substantially increase the water content of existing hair spray products. However, for water-insoluble polymers, such as GANTREZ.RTM.-ES resins, which do not dissolve readily in water-based systems, such changes produce two-phase systems, which is undesirable from a commercial standpoint.
Accordingly, it is an object of the present invention to provide a 0% VOC hair spray composition containing a water-insoluble polymer in the form of a single phase system.
Another object of the invention is to provide a 0% VOC, single phase hair spray composition which includes a water-insoluble polymer, a surfactant and water, and in which substantially all the particles therein have a diameter of less than 1 micron.
Still another object of the present invention is the provision of a clear, single phase, pumpable or propellant-actuated, 0% VOC hair spray composition including the ethyl half-ester of a copolymer of maleic anhydride and methyl vinyl ether as the hair fixative, a surfactant and water, and, optionally, a non-VOC cosolvent.
A particular object of the invention is to provide a clear, single phase, 0% VOC hair spray composition of a water-insoluble fixative resin in the form of a microemulsion.
These and other objects and features of the invention will be made apparent from the following more particular description of the invention.